<template>
  <Select
    @dropdown-visible-change="handleFetch"
    v-bind="attrs"
    @change="handleChange"
    :options="getOptions"
    v-model:value="state"
  >
    <template #[item]="data" v-for="item in Object.keys($slots)">
      <slot :name="item" v-bind="data || {}"></slot>
    </template>
    <template #suffixIcon v-if="loading">
      <LoadingOutlined spin />
    </template>
    <template #notFoundContent v-if="loading">
      <span>
        <LoadingOutlined spin class="mr-1" />
        {{ t("component.form.apiSelectNotFound") }}
      </span>
    </template>
  </Select>
</template>
<script lang="ts">
import { defineComponent, PropType, ref, watchEffect, computed, unref, watch } from "vue";
import { Select } from "ant-design-vue";
import { isFunction } from "/@/utils/Is";
import { useRuleFormItem } from "/@/hooks/component/UseFormItem";
import { useAttrs } from "/@/hooks/core/UseAttrs";
import { get, omit } from "lodash-es";
import { LoadingOutlined } from "@ant-design/icons-vue";
import { useI18n } from "/@/hooks/web/UseI18n";
import { propTypes } from "/@/utils/PropTypes";

type OptionsItem = { label: string; value: string; disabled?: boolean };

export default defineComponent({
  name: "ApiSelect",
  components: {
    Select,
    LoadingOutlined
  },
  // inheritAttrs: false,
  props: {
    value: [Array, Object, String, Number],
    numberToString: propTypes.bool,
    api: {
      type: Function as PropType<(arg?: Recordable) => Promise<OptionsItem[]>>,
      default: null
    },
    // api params
    params: propTypes.any.def({}),
    // support xxx.xxx.xx
    resultField: propTypes.string.def(""),
    labelField: propTypes.string.def("label"),
    valueField: propTypes.string.def("value"),
    immediate: propTypes.bool.def(true),
    alwaysLoad: propTypes.bool.def(false)
  },
  emits: ["options-change", "change", "update:value"],
  setup(props, { emit }) {
    const options = ref<OptionsItem[]>([]);
    const loading = ref(false);
    const isFirstLoad = ref(true);
    const emitData = ref<any[]>([]);
    const attrs = useAttrs();
    const { t } = useI18n();
    // 嵌入表单中，只需使用钩子绑定执行表单验证
    const [state] = useRuleFormItem(props, "value", "change", emitData);
    const getOptions = computed(() => {
      const { labelField, valueField, numberToString } = props;
      return unref(options).reduce((prev, next: Recordable) => {
        if (next) {
          const value = next[valueField];
          prev.push({
            ...omit(next, [labelField, valueField]),
            label: next[labelField],
            value: numberToString ? `${value}` : value
          });
        }
        return prev;
      }, [] as OptionsItem[]);
    });

    watchEffect(() => {
      props.immediate && !props.alwaysLoad && fetch();
    });

    watch(
      () => state.value,
      (v) => {
        emit("update:value", v);
      }
    );

    watch(
      () => props.params,
      () => {
        !unref(isFirstLoad) && fetch();
      },
      { deep: true }
    );

    async function fetch() {
      const api = props.api;
      if (!api || !isFunction(api)) return;
      options.value = [];
      try {
        loading.value = true;
        const res = await api(props.params);
        if (Array.isArray(res)) {
          options.value = res;
          emitChange();
          return;
        }
        if (props.resultField) {
          options.value = get(res, props.resultField) || [];
        }
        emitChange();
      } catch (error) {
        console.warn(error);
      } finally {
        loading.value = false;
      }
    }

    async function handleFetch(visible) {
      if (visible) {
        if (props.alwaysLoad) {
          await fetch();
        } else if (!props.immediate && unref(isFirstLoad)) {
          await fetch();
          isFirstLoad.value = false;
        }
      }
    }

    function emitChange() {
      emit("options-change", unref(getOptions));
    }

    function handleChange(_, ...args) {
      emitData.value = args;
    }

    return { state, attrs, getOptions, loading, t, handleFetch, handleChange };
  }
});
</script>
